Seroprevalence of SARS-CoV-2 antibodies among 925 staff members in an urban hospital accepting COVID-19 patients in Osaka prefecture, Japan: A cross-sectional study.

ABSTRACT: The subclinical severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rate in hospitals during the pandemic remains unclear. To evaluate the effectiveness of our hospital's current nosocomial infection control measures, we conducted a serological survey of anti-SARS-CoV-2 antibodies (immunoglobulin [Ig] G) among the staff of our hospital, which is treating coronavirus disease 2019 (COVID-19) patients.The study design was cross-sectional. We measured anti-SARS-CoV-2 IgG in the participants using a laboratory-based quantitative test (Abbott immunoassay), which has a sensitivity and specificity of 100% and 99.6%, respectively. To investigate the factors associated with seropositivity, we also obtained some information from the participants with an anonymous questionnaire. We invited 1133 staff members in our hospital, and 925 (82%) participated. The mean age of the participants was 40.0 ±â€Š11.8 years, and most were women (80.0%). According to job title, there were 149 medical doctors or dentists (16.0%), 489 nurses (52.9%), 140 medical technologists (14.2%), 49 healthcare providers (5.3%), and 98 administrative staff (10.5%). The overall prevalence of seropositivity for anti-SARS-CoV-2 IgG was 0.43% (4/925), which was similar to the control seroprevalence of 0.54% (16/2970) in the general population in Osaka during the same period according to a government survey conducted with the same assay. Seropositive rates did not significantly differ according to job title, exposure to suspected or confirmed COVID-19 patients, or any other investigated factors.The subclinical SARS-CoV-2 infection rate in our hospital was not higher than that in the general population under our nosocomial infection control measures.

Effects of Febuxostat on Oxidative Stress.

PURPOSE: We previously examined factors that affect the measured derivatives of reactive oxygen metabolites (d-ROMs), an indicator of reactive oxygen species production, and biological antioxidant potential (BAP), an indicator of antioxidant capacity, in typical health checkup examinees and reported the usefulness of measuring both indicators simultaneously. In addition, a positive correlation reportedly exists between d-ROMs and the visceral fat area measured by using computed tomography. A recent study of the relationship between uric acid levels and various obesity-related factors found that visceral fat was the factor most strongly related to uric acid levels. Uric acid is itself a potent endogenous antioxidant, but because reactive oxygen species are produced during uric acid generation, it is suggested that uric acid may have opposing effects. The objective of this study was to analyze the effect of febuxostat, a novel xanthine oxidase inhibitor, on oxidative stress. METHODS: Study subjects were 43 hyperuricemia outpatients receiving care in the internal medicine department of our institution. The subjects were divided into a new administration group (29 patients) and a switched administration group (14 patients); the latter were allopurinol-treated patients with hyperuricemia who were switched to febuxostat. In addition to measuring the patients' uric acid and creatinine levels and estimated glomerular filtration rate before and after treatment, their d-ROMs and BAP as well as the BAP/d-ROMs ratio were also measured. FINDINGS: Both groups exhibited significant decreases in uric acid levels, as well as significant decreases in d-ROMs and BAP. No significant changes were observed in the BAP/dROMs ratio or renal function, including creatinine levels and estimated glomerular filtration rate. IMPLICATIONS: Febuxostat could significantly reduce d-ROMs. However, BAP levels were also significantly reduced concurrently. No changes were observed in the BAP/d-ROMs ratios. This regulatory mechanism is believed to have counteracted changes in the in vivo oxidative stress balance caused by febuxostat administration.

Significance of measuring oxidative stress in lifestyle-related diseases from the viewpoint of correlation between d-ROMs and BAP in Japanese subjects.

In recent years, oxidative stress has been postulated to be an important factor in the pathogenesis and development of lifestyle-related diseases. In this study, we investigated the association between the derivatives of reactive oxygen metabolites (d-ROMs), as an index of products of reactive oxygen species (ROS), and biological antioxidant potential (BAP), as an index of antioxidant potential. We also investigated the associations between d-ROMs or BAP and the risk factors for lifestyle-related diseases or metabolic syndrome-associated factors to evaluate their usefulness in preventive medicine. There were 442 subjects who underwent health checkup examination in our facilities. In addition to standard medical checkup items, we analyzed d-ROMs, BAP, brachial-ankle pulse wave velocity, high-sensitivity C-reactive protein level and visceral fat area (VFA) visualized on a computed tomography scan. The mean d-ROM value in females was significantly higher than that in males. There was a positive correlation between the d-ROM and VFA levels. On correlation analysis, there was a negative correlation between the d-ROM and creatinine levels. As factors that influence d-ROMs, the level of VFA was selected, suggesting the significance of oxidative stress measurement with d-ROMs. In addition, there was a positive correlation between d-ROMs and BAP values. Further research is required to resolve whether increased production of ROS or the antioxidant potential that can compensate for such an increase of ROS is more important in vivo.

Switching from altro-alpha-cyclodextrin dimer to pseudo[1]rotaxane dimer through tumbling.

An alkyl altro-alpha-CD dimer was converted to the pseudo[1]rotaxane dimer through tumbling of the altropyranose unit of altro-alpha-CD in D(2)O. The tumbling of the altropyranose unit was found to be a rotational vibration with 1.18 x 10(-3) s(-1) at 293 K. The activation free energy (DeltaG(double dagger)(288K)) for the conformational change from an alkyl altro-alpha-CD dimer to pseudo[1]rotaxane dimer was 88.0 kJ mol(-1), which corresponds to the breakage of the hydrogen bond network for the tumbling of an altropyranose unit.

A molecular reel: shuttling of a rotor by tumbling of a macrocycle.

A molecular shuttle is a prototype of molecular machines capable of shuttling a part back and forth in the molecule. To control the shuttling of a macrocycle, we studied the reeling of an axis molecule into a macrocyclic host molecule located at the end of the axis. [2]Rotaxane and [3]rotaxane are composed of alpha-cyclodextrin (alpha-CD) rotors, a decamethylene chain, and a stilbene unit as axes and an altro-alpha-CD stopper containing one altropyranose unit and five glucopyranose units. The alpha-CD rotor of [2]rotaxane includes the decamethylene chain in DMSO-d(6) and moves to include the stilbene group in D(2)O. It should be noted that the altro-alpha-CD stopper group reorients to include the decamethylene chain in D(2)O. The mechanism for tumbling was elucidated with 2D ROESY NMR measurements and kinetic studies. These studies showed that an altropyranose unit of the altro-alpha-CD stopper tumbles to form a self-inclusion complex in aqueous solution. The altro-alpha-CD stopper of [2]rotaxane reels an axis molecule into its cavity and then pushes the alpha-CD rotor onto the stilbene group, resulting in conversion to pseudo[2]rotaxane in D(2)O. In contrast, the rotors of [3]rotaxane did not show shuttling because there was insufficient space not only for the rotors to shuttle but also for the altro-alpha-CD stopper to include an axis after tumbling. The decamethylene chain and the stilbene group are already included in the rotors of [3]rotaxane. The tumbling of the altro-alpha-CD stopper was found to play a critical role in controlling the shuttling of rotors. We successfully controlled the shuttling of a rotor by reeling the axis molecule into a host molecule at the end of an axis.

Switching between supramolecular dimer and nonthreaded supramolecular self-assembly of stilbene amide-alpha-cyclodextrin by photoirradiation.

3-trans-Stilbene amide-alpha-cyclodextrin (3-trans-Sti-alpha-CD) formed a double-threaded dimer in aqueous solutions. In contrast, the photoisomerization of the stilbene moiety in 3-Sti-alpha-CD from trans to cis leads to the structural changes from the double-threaded dimer to nonthreaded supramolecular assemblies in aqueous solutions. The structures of these supramolecular complexes have been found to be controllable by photoirradiation.

Clinical significance of immunocytochemistry for PIK3CA as a carcinogenesis-related marker on liquid-based cytology in cervical intraepithelial neoplasia.

The catalytic subunit alpha of phosphatidylinositol 3-kinase (PIK3CA) has been expected to play a role as an important oncogene in uterine cervical carcinoma, whose expression in non-invasive lesions has received considerable attention. We investigated the potential of PIK3CA as a carcinogenesis-related marker for early intraepithelial lesion of the uterine cervix in cytology samples. Seventy-four cases with abnormal cytology suggesting the existence of cervical intraepithelial neoplasia (CIN) lesions, whose findings were histologically confirmed, were selected; they consisted of 20 CIN1, 21 CIN2, and 33 CIN3, respectively. In addition, 17 normal cases, whose cervical cytology revealed no abnormality over three occasions, were selected. Liquid-based cytology specimens were applied for human papillomavirus (HPV) DNA typing and immunocytochemistry using three different antibodies for p16(INK4a), Ki-67 and PIK3CA, respectively. The fraction of immunopositive cells on the slides was calculated and expressed as mean numbers. Receiver operating characteristic (ROC) plots were generated to determine the diagnostic accuracy of each immunocytochemistry test. The mean number of immunopositive cells in the CIN3 group was significantly higher than other groups for all three antibodies. Among all groups, PIK3CA showed a superior specificity to distinguish CIN3 from other groups. Comparison of three markers by ROC curves also revealed that PIK3CA provided the best method for distinguishing CIN3. Thus, expression of PIK3CA was observed in liquid-based cytology in CIN lesions, which suggested its diagnostic significance in addition to the use of routine cervical cancer smear and the HPV screening program.